It is somewhat difficult to remotely control the speed or engine speed of a vehicle.
One commonly used method for stopping a vehicle having rubber tires involves the placement of a spike belt in the vehicle's path (belts having a number of hollow cylinders which puncture the tire and cause deflation in a controlled manner). However, this requires the spike belt be laid in the vehicle's path, does result in reduced control of the vehicle and only works with vehicles having tires (e.g. not for example, with tracked vehicles such as earth movers such as bulldozers or military vehicles such as armored personnel carriers).
Another method involves the sending of an electromagnetic pulse or energy wave at the vehicle to interfere with its electronic circuits. However, this requires close proximity to the vehicle and does not work with vehicles that do not rely heavily on electronics, for example large diesel engines in transport trucks.
Idle speed may be set manually, and timers have been deployed to limit time-at-idle, also set manually.
It is, therefore, desirable to provide a vehicle control unit that provides for safely controlling the maximum speed of a vehicle or of its engine and the engine's maximum time-at-idle.